Embed Size (px)
Citation preview
2014 System Operator Conference
1
Protection System Misoperations:Why Should a System Operator Give a Hoot?
April 17 & May 1, 2014 – Charlotte, NCSeptember 11 & 25, 2014 – Nashville/Franklin, TN
David Greene, P.E.Senior Reliability Engineer
SERC Reliability Corporation
2014 System Operator Conference
Learning Objectives
• Explain how Protection System Misoperations impact the Bulk Electric System (BES).
• State the process for addressing Protection System Misoperations per the PRC-004 NERC Reliability Standard.
• List the common categories of Protection System Misoperations and name some common causes.
• Identify ways in which Protection System Misoperations can impact System Operators (per PRC-001 requirements).
• Recognize what is and is not a Protection System Misoperation from actual examples.
2
At the conclusion of this training session, you should be able to:
2014 System Operator Conference
Outline of Topics Explain Applicable PRC Standards PRC-001 & PRC-004 Misoperation Reporting Process Misoperation Categories Misoperation Causes Example 1 – Failure to Trip Example 2 – Unnecessary Trip with Fault Example 3 – Unnecessary Trip without Fault Example 4 – Human error Example 5 – Slow Trip Example 6 – Special Protection System Fail to Operate Example 7 – AZ/CA Blackout – SPS Coordination? Examples 8-10 more Unnecessary Trip with Fault Summary of Main Points
3
2014 System Operator Conference
Understanding the Intent of PRC - 001
System Operator Can you handle the Truth???
We need you on that Wall
Actually, you are on the wall whether or not you realize it
4
2014 System Operator Conference
Understanding the Intent of PRC - 004
Protection System Misoperations will happen
FIX THEM!
And by the way, don’t dilly dally around getting it done!
5
2014 System Operator Conference
Misoperation Reporting Process
1. Misoperation occurs2. TO, GO, DP analyzes misoperation3. TO, GO, DP develops Corrective Action Plan (CAP)4. TO, GO, DP implements CAP5. TO, GO, DP reports misoperations and CAP status
quarterly6. Region (SERC Protection and Controls Subcommittee
PCS) reviews misoperations and operations reporting
7. Region provides misoperations and operations data to NERC after Region review
8. Region monitors timeliness of CAP implementation 6
2014 System Operator Conference
Four Misoperation Categories
Presented in order of increasing occurrences:
• Slow Trip• Failure to Trip• Unnecessary Trip without a Fault• Unnecessary Trip with a Fault
7
2014 System Operator Conference
Ten Misoperation Causes
1. AC system2. As-left personnel error3. Communication failures4. DC system5. Incorrect settings6. Logic error7. Design error8. Relay failures/malfunctions9. Unknown/unexplainable10.Other/explainable
8
2014 System Operator Conference
Oakboro Tie
Monroe Main Albemarle Sw. Sta.
Radial Load
Line
A
Line
B
Line
C
230 kV
100 kV
44 kV
T=0.000+ sec
Line
D
Bank 1 Bank 2 Bank 3
Line
E
Line
F
4 - 230kV Network Lines
Radial Load
Fault 2.7 miles from Oakboro
Z-Grd fault
Line Faul
t
Misoperation Example 1:
Failure to Trip
Line Faul
t
What the heck?
9
2014 System Operator Conference
Misoperation Example 2:Unnecessary Trip with Fault
X
01
Station A
0605
040302
Station D
Station C
Station B
Line Fault
Why trip?
10
2014 System Operator Conference
Misoperation Example 3: Unnecessary Trip without Fault
Generator trip
Why separate from the grid?
11
2014 System Operator Conference
10
12
04
06
07
08
W
BUS 2: Cleared to install capacitor
01
02
0309
Misoperation Example 4:Human Error
BUS 1
NOT A Misoperation
12
2014 System Operator Conference
Misoperation Example 5: Slow Trip
X
04
Station B
0201 03
Station EStation D
Station C
Line FaultWhy trip?
G G
W
Station A
13
2014 System Operator Conference
WW
L1
TX1 TX 2
L4L3L2Out of Service
G1 G2
500kV
200kV
X Line
Fault and Lockout
Unit Supposed to Trip
Misoperation Example 6:Special Protection System (SPS)Failure to Operate
Line Overload, Instability
Line Overload
14
2014 System Operator Conference
L3
Misoperation Example 7: AZ/CA Outage - SPS Lack of Coordination
L2 L4
Note: Drawing copied from the FERC, NERC AZ/CA Sept 8, 2011 Outage Report
AZ/CA Blackout was initiated by a Switching Error, not a misoperation
15
2014 System Operator Conference
Example 7 Cont’d: AZ/CA Outage - SPS Lack of Coordination
Note: Drawing copied from the FERC, NERC AZ/CA Sept 8, 2011 Outage Report
• “S” Line Remedial Action Scheme (SPS) operated too soon• SONGS Separation Scheme (SPS) – Lack of Coordination• Protection Settings to close to Facility Emergency Ratings
16
2014 System Operator Conference
10
12
04
06
07
08
09Open for Maint.
STA 3W
BUS 1
BUS 2
01
02
03
STA 441 42
13 14
21 22STA 2
31 32
Misoperation Example 8:Unnecessary Trip with Fault
Insulator failure
X
Why trip?
Why trip?
17
2014 System Operator Conference
07
09
STA C
04
05
06
STA BW
BUS 2
01
02
03
STA DSTA B
Misoperation Example 9:Unnecessary Trip with Fault
BUS 1
Why 01 and 07 trip?
18
X
X Line Fault
Line Fault
2014 System Operator Conference
Misoperation Example 10: Unnecessary Trip with Fault
X
04
Station B
0201
05
03
Station EStation D
Station C
Temporary Line Fault
Why 03,04,05 trip?
G G
W
Station A
19
2014 System Operator Conference
Learning Objectives Met?
1. How do Protection System Misoperations impact the Bulk Electric System (BES)?
2. Which NERC Reliability Standard(s) address Protection System Misoperations?
3. What are the four categories of Protection System Misoperations?
4. Name three of the ten causes for Protection System Misoperations?
5. How do Protection System Misoperations impact System Operators?
20
Can you answer:
2014 System Operator Conference
SummaryThe main points of this training session are:
• Protection System Misoperations happen – Fix them!
• PRC-004 identifies requirements for analyzing, reporting and correcting misoperations – Comply!
• System Operators get to deal with the results of Protection System Misoperations so:
• YOU shall know the purpose and limitations of Protection Systems schemes applied in your area! (PRC-001, Requirement 1).
21
